Nexplanon

"Nov. 20, 2012 -- Oral contraceptives should be made available without a prescription to reduce unintended pregnancies, according to a newly published opinion by the American College of Obstetricians and Gynecologists (ACOG).

Clinical Trials Experience

Because clinical trials are conducted under widely
varying conditions, adverse reaction rates observed in the clinical trials of a
drug cannot be directly compared to rates in the clinical trials of another
drug and may not reflect the rates observed in practice.

In clinical trials involving 942 women who were evaluated
for safety, change in menstrual bleeding patterns (irregular menses) was the
most common adverse reaction causing discontinuation of use of the
non-radiopaque etonogestrel implant (IMPLANON) (11.1% of women).

Adverse reactions that resulted in a rate of
discontinuation of ≥ 1% are shown in Table 3.

Table 3: Adverse Reactions Leading to Discontinuation
of Treatment in 1% or More of Subjects in Clinical Trials of the Non-Radiopaque
Etonogestrel Implant (IMPLANON)

Adverse Reactions

All Studies
N = 942

Bleeding Irregularities*

11.1%

Emotional Lability†

2.3%

Weight Increase

2.3%

Headache

1.6%

Acne

1.3%

Depression‡

1.0%

* Includes “frequent”, “heavy”,
“prolonged”, “spotting”, and other patterns of bleeding irregularity.
†Among US subjects (N=330), 6.1% experienced emotional lability that led to
discontinuation.
‡Among US subjects (N=330), 2.4% experienced depression that led to
discontinuation.

Other adverse reactions that
were reported by at least 5% of subjects in the non-radiopaque etonogestrel
implant clinical trials are listed in Table 4.

Table 4: Common Adverse Reactions Reported by
≥ 5% of Subjects in Clinical Trials With the Non-Radiopaque Etonogestrel
Implant (IMPLANON)

Adverse Reactions

All Studies
N = 942

Headache

24.9%

Vaginitis

14.5%

Weight increase

13.7%

Acne

13.5%

Breast pain

12.8%

Abdominal pain

10.9%

Pharyngitis

10.5%

Leukorrhea

9.6%

Influenza-like symptoms

7.6%

Dizziness

7.2%

Dysmenorrhea

7.2%

Back pain

6.8%

Emotional lability

6.5%

Nausea

6.4%

Pain

5.6%

Nervousness

5.6%

Depression

5.5%

Hypersensitivity

5.4%

Insertion site pain

5.2%

In a clinical trial of
NEXPLANON, in which investigators were asked to examine the implant site after
insertion, implant site reactions were reported in 8.6% of women. Erythema was
the most frequent implant site complication, reported during and/or shortly
after insertion, occurring in 3.3% of subjects. Additionally, hematoma (3.0%),
bruising (2.0%), pain (1.0%), and swelling (0.7%) were reported.

Postmarketing Experience

The following additional
adverse reactions have been identified during post-approval use of the
non-radiopaque etonogestrel implant (IMPLANON). Because these reactions are
reported voluntarily from a population of uncertain size, it is not possible to
reliably estimate their frequency or establish a causal relationship to drug
exposure.

DRUG INTERACTIONS

Changes In Contraceptive
Effectiveness Associated With Coadministration Of Other Products

Drugs or herbal products that
induce enzymes, including CYP3A4, that metabolize progestins may decrease the
plasma concentrations of progestins, and may decrease the effectiveness of
NEXPLANON. In women on long-term treatment with hepatic enzyme inducing drugs,
it is recommended to remove the implant and to advise a contraceptive method
that is unaffected by the interacting drug.

Some of these drugs or herbal
products that induce enzymes, including CYP3A4, include:

barbiturates

bosentan

carbamazepine

felbamate

griseofulvin

oxcarbazepine

phenytoin

rifampin

St. John's wort

topiramate

HIV Antiretrovirals

Significant changes (increase or decrease) in the plasma levels
of progestin have been noted in some cases of coadministration with HIV protease inhibitors or with non-nucleoside reverse transcriptase inhibitors.
Consult the labeling of all concurrently-used drugs to obtain further
information about interactions with hormonal contraceptives or the potential
for enzyme alterations.

Increase In Plasma Concentrations Of Etonogestrel
Associated With Coadministered Drugs

CYP3A4 inhibitors such as itraconazole or ketoconazole
may increase plasma concentrations of etonogestrel.

Changes In Plasma Concentrations Of Coadministered Drugs

Hormonal contraceptives may affect the metabolism of
other drugs. Consequently, plasma concentrations may either increase (for
example, cyclosporin) or decrease (for example, lamotrigine). Consult the
labeling of all concurrently-used drugs to obtain further information about
interactions with hormonal contraceptives or the potential for enzyme
alterations.

Last reviewed on RxList: 6/13/2014
This monograph has been modified to include the generic and brand name in many instances.